1. Field of the Invention
The present invention relates to loading and unloading methods of a test handler that assists a tester to test the produced semiconductor devices.
2. Description of the Related Art
A test handler is a piece of equipment that loads semiconductor devices manufactured by a certain process onto a test tray, assists a tester to test the semiconductor devices loaded onto the test tray, sorts the semiconductor devices according to the test result, and then unloads the semiconductor devices from the test tray onto customer trays. Technology related to the test handler has been disclosed through many publications, such as a Korean Patent No. 10-0553992 (hereinafter, referred to as a conventional art).
In general, the produced semiconductor devices are loaded onto customer trays and then transferred to the test handler. The semiconductor devices are loaded from customer trays onto a test tray located at a loading position within the test handler. The semiconductor devices loaded onto the test tray are moved through a test position to an unloading position and then unloaded onto customer trays.
While the semiconductor devices are moving within the test handler, they are tested at the test position by a tester docked to the test handler.
FIG. 1 is a schematic plan view illustrating a general customer tray (C.T) and FIG. 2 is a schematic plan view illustrating a general test tray (T.T).
As shown in FIG. 1, the customer tray (C.T) forms a plurality of loading compartments (CS) arrayed in a matrix form. As shown in FIG. 2, the test tray (T.T) also forms a plurality of loading compartments (TS) arrayed in a matrix form. For ease of description, the loading compartments (TS) of the test tray (T.T) are hereinafter referred to as “placing compartments (TS).”
The customer tray (C.T), in general, serves to carry and store semiconductor devices. To this end, the customer tray (C.T) is designed to have a minimized spacing between the loading compartments (CS) in order to load as many semiconductor devices as possible. On the contrary, since the test tray (T.T) serves to assist the tester to test the semiconductor devices, it secures a spacing between the placing compartments (TS) in such a way that the semiconductor devices loaded onto the test tray (T.T) can be tested without interference. Therefore, the inter-row spacing (aC) and the inter-column spacing (bC) between the loading compartments (CS) of the customer tray (C.T) are smaller than the inter-row spacing (aT) and the inter-column spacing (bT) between the placing compartments (TS) of the test tray (T.T), correspondingly and respectively.
The test handler includes a pick-and-place apparatus that loads semiconductor devices from a customer tray (C.T) onto a test tray (T.T) or unloads semiconductor devices from a test tray (T.T) onto a customer tray (C.T). The pick-and-place apparatus is also referred to as a loader hand, unloader hand, loader, or unloader, etc. The pick-and-place apparatus is configured to include a plurality of pickers generally arrayed in a matrix, in which one picker picks up one semiconductor device. Such a configuration of the pick-and-place apparatus makes it possible to transfer as many semiconductor devices as possible during one operation.
To this end, the pick-and-place apparatus must have a pitch regulation apparatus that regulates the pitch between the plurality of pickers to the spacing between the loading compartments (CS) of the customer tray (C.T) or the spacing between the placing compartments (TS) of the test tray (T.T).
If the pickers are arrayed in two rows or columns in the pick-and-place apparatus, the pitches between the two rows or between the two columns of the pickers can be regulated only by cylinder piston units. On the contrary, if the pickers are arrayed in three or more rows or columns, a cam system or a link system must be used to regulate the pitches between the rows or between the columns of the pickers. For reference, the cam system is employed by most of the test handlers produced by MIRAE Company, and the link system is used by most of the test handlers produced by TECHWING Company.
However, both the cam system and the link system cause an increase in the weight of the pick-and-place apparatus. If the pick-and-place apparatus becomes too heavy, its mobility is decreased so that it cannot perform a loading or unloading operation at a high speed. To prevent such a problem, the conventional pick-and-place apparatus is configured in such a way that the pickers are arrayed in a 2×N matrix (N>2), in which the pitches between the columns of the pickers are regulated by a cam system or a link system and the pitches between the rows of the pickers are regulated by cylinder piston units. Through such a configuration, the conventional pick-and-place apparatus achieves the aim of transferring a number of semiconductor devices, during one operation, and also achieves the objective of operating at a high speed.
In addition, the conventional art is implemented by another test tray (T.T) as shown in FIG. 3. The test tray (T.T) is configured in such a way that the placing compartments (TS) can be regularly arrayed in two different inter-row spacings (aT1 and aT2). When the conventional pick-and-place apparatus includes three or more rows of the pickers, the pitches between the respective rows of the pickers must be possible to be regulated from the spacing (ac) between the rows of the loading compartments (CS) of the customer tray (C.T) to the spacings (aT1 and aT2) between the rows of the placing compartments (TS) of the test tray (T.T), or vice versa. However, this configuration makes the pick-and-place apparatus complicated and causes an increase in the number of parts. Therefore, the conventional pick-and-place apparatus cannot be implemented three or more rows.
That is, the conventional pick-and-place apparatus must be configured as a structure of only two rows of the pickers and accordingly cannot perform a loading or unloading operation at a high speed. Therefore, a new method is required to overcome these problems.